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Water heater with element in the top section - bad?

  1. May 27, 2014 #1
    I've got a 300 liter water heater that has an electrical element (14 kW). The issue is that the element is positioned in the top third of the heater. I fear the water will become segregated so that only water in the top third will be heated, and the lower section will remain cold. The target temperature is 65°C and the entering water will be around 30°C. What do you think?
  2. jcsd
  3. May 27, 2014 #2


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    Staff: Mentor

    I thought they typically had elements both in the top and bottom section. Do you have the model number?
  4. May 27, 2014 #3
    I don't have it readily available, but I'm sure the only element is in the top section of the tank.
  5. May 29, 2014 #4


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    Science Advisor
    Gold Member

    The water heaters I have dealt with have an upper and lower element. They are 4500 watts each and are never on at the same time. There is an upper and lower thermostat as well. Cold water enters the bottom and hot water is taken off the top. The lower thermostat will naturally be the first to come on. Typically if not a lot of water is used at one time it will be the only one that ever runs. If a lot of hot water is used then the bottom element will not keep up and when the top cools enough it will turn on and it will also switch the bottom one off. Never heard of a water heater with only one element unless it is a small 5 gallon heater.
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